THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

WOLF BLITZER, CNN ANCHOR: Not a hoax! We're learning disturbing new information about the bombs, which experts are analyzing. The FBI says they are not hoax devices, and warns more of them could be in the mail right now.

[17:00:43] Anger and hate. The suspect revealed to be an avid Trump supporter, whose van and social media accounts are filled with partisan, hate-filled rhetoric targeting CNN, Democrats and others he believes oppose the president.

And shunning responsibility. Mr. Trump refusing to acknowledge that his own divisive rhetoric is poisoning the political climate and may have motivated the bombing suspect. He still hasn't mentioned the intended victims by name and hasn't reached out to the two former presidents targeted for assassination.

I'm Wolf Blitzer. You're in THE SITUATION ROOM.

ANNOUNCER: This is CNN breaking news.

BLITZER: We're following breaking news. The arrest of a Florida man, suspected of sending at least 13 explosive devices in an attempted bombing spree that stretched from coast to coast.

Fifty-six-year-old Cesar Sayoc, a fervent Trump supporter, believed to be living out of a van plastered with virulent messages against CNN and Democrats, the targets of the bombs, which the FBI says were real.

First, let's get the very latest on the breaking news. Our chief national security correspondent, Jim Sciutto, is joining us.

Jim, we're learning a lot more about this suspect.

JIM SCIUTTO, CNN CHIEF NATIONAL SECURITY CORRESPONDENT: No question, Wolf. Quite a day. Extremely fast-moving events. It started with two more bombs sent to senator Cory Booker, then to former DNI Jim Clapper, addressed to CNN in New York. Those packages intercepted, thankfully, and more targets later in the day.

But the key: the FBI getting their man. Incredibly quick work over these last several days. And the key, some DNA, a fingerprint left behind on at least one of these devices.

CHRISTOPHER WRAY, FBI DIRECTOR: We can confirm that 13 IEDs were sent to various individuals across the country.

These are not hoax devices.

SCIUTTO: Sources say investigators used his cell phone to track him after DNA evidence was found on some of the packages. In addition --

WRAY: They uncovered a latent fingerprint from one of the envelopes containing an IED that had been sent to Congresswoman Maxine Waters.

SCIUTTO: One of the reasons authorities arrested him in a public place was because an address associated with him in Florida might pose a danger to officers if there were explosives present.

Officials say that he was living with his parents, but they had kicked him out and so was living out of his van, which authorities took into custody after he was arrested. The van covered in political decals, images of the president and vice president, one saying, "CNN sucks."

UNIDENTIFIED MALE: CNN sucks! CNN sucks!

UNIDENTIFIED MALE: CNN sucks! CNN sucks!

UNIDENTIFIED MALE: CNN sucks! CNN sucks!

SCIUTTO: A frequent chant at the president's rallies.

Sayoc attended one of those rallies in Melbourne, Florida, in 2017, and held a sign with the same message. His Twitter account included memes attacking billionaire investor George Soros, one of the targets of the alleged bombings.

Online records show that Sayoc had an extensive arrest record across two states, including grand theft, battery, fraud, drug possession, and one in Miami in 2002. According to a police report he threatened to blow up a Florida utility company "worse than September 11." He pleaded guilty and was sentenced to a year of probation.

He now faces five federal charges, and up to 48 years in prison.

GEOFFREY BERMAN. U.S. ATTORNEY, SOUTHERN DISTRICT OF NEW YORK: The defendant's conduct as charged is cowardly and reprehensible and totally anathema to our democracy.

SCIUTTO: But the threat may not be over. Even after Sayoc was arrested, another suspicious package was intercepted in California. Authorities say this one was addressed to major Democratic donor, Tom Steyer. And authorities are concerned that more suspicious packages could be in the mail.

WRAY: Today's arrest doesn't mean we're all out of the woods. There may be other packages in transit now.

[17:05:04] SCIUTTO: Earlier in the day, police had discovered three other similar suspicious packages, addressed to Democratic senators Cory Booker and Kamala Harris, as well as former director of national intelligence and CNN contributor James Clapper. That package addressed to CNN's New York office.

There have been questions throughout the week about the seriousness of the threat from these devices. Were they capable of exploding? Was that the intention?

But Wolf, you heard from the FBI director there and others commenting on this. They say very definitively, they call them IEDs, improvised explosive devices. That's a term they use in Iraq and Afghanistan for devices used and deployed by terrorists. And as he said there, in the clearest terms possible, the FBI director, these were not hoax devices.

BLITZER: Yes. He did not mince any words, Christopher Wray, the FBI director. IEDs, as you point out, improvised explosive devices, not a hoax. Stand by, Jim.

Evan, what do we know about this guy's record? He's got a criminal record, and he's been -- he's been charged in the past with several crimes.

EVAN PEREZ, CNN JUSTICE CORRESPONDENT: Right, exactly. He's been arrested at least nine times, most of those in Florida, dating back 20 years in Florida there, Wolf.

And one of the -- one of his charges is bomb-related charge. I think it was threatening to bomb a utility down there in Florida. So there was some history.

And let me tell you. That was a key part of this. That was a huge part of why the FBI was able to solve this very quickly. Because, as Jim pointed out, there was a couple of pieces of -- two of these IEDs -- one that was being mailed to Maxine Waters, the congresswoman, and another one that was being mailed to Barack Obama, the former president -- had his DNA. So they were able to match it to records that they already had. They also found a fingerprint in one of the IEDs that was being sent to Maxine Waters. Again, they were able to compare that to fingerprints that he had from his previous arrest record.

So the fact that he had a rap sheet a mile long was extremely helpful in this investigation for the FBI.

BLITZER: And as soon as they found the fingerprint on the package sent to Maxine Waters, they apparently had their guy pretty quickly. It was not hard to find him.

Shimon, what have we learned about these improvised explosive devices, as Christopher Wray calls them? How were they made, and were they armed?

SHIMON PROKUPECZ, CNN CRIME AND JUSTICE CORRESPONDENT: Yes, so the FBI director explained at the press conference and also in the court documents, basically, the way they're described, they're six inches of PVC piping. There was a small clock, according to the FBI director. Batteries, wiring. And there was energetic material. That's the explosive material that was all in these bombs. It was all contained in these devices.

The question that they're not answering right now is where were these made, and how did he know how to make this?

What's interesting is, as Evan's been reporting, he was thrown out of his mother's house. He was living in a van. So where would he have put these together? And where would he have learned, or perhaps it could have been on the Internet. Where would he have gone to know, to learn how to put this together?

That's not answered right now in any of these court documents, Wolf.

BLITZER: You know, Josh, you used to work at the FBI. Take us inside the lab over there at Quantico, Virginia, where these -- these bombs were taken. How did they actually discover the DNA, the fingerprints that led to the arrest?

JOSH CAMPBELL, CNN LAW ENFORCEMENT ANALYST: So, Wolf, there are different ways of actually disrupting a potential, dangerous device like an explosive.

Now, when we think about the initial incident that we saw with George Soros, authorities actually disrupted that on site and rendered it safe. Once it appeared that there were a number of different devices that were now in play, they wanted to try to preserve that evidence.

They shipped them back to the FBI's laboratory at Quantico, and basically, the capabilities and facilities there allow them to essentially conduct surgery on a device: to take it apart, to figure out what is there, what the components are.

But just as important, Wolf, as you mentioned, they can actually also look for DNA, hair fibers, evidence that may be helpful in linking this back to a particular person. That's all part of that critical analysis. And here, at least, it shows that that actually played a pivotal role in identifying the subject.

BLITZER: You know, Pamela, you had a chance, you were at the news conference with the attorney general and the others, the FBI director. You had a chance to ask about the suspect's social media posts and how they were related and what it says about his political motives.

PAMELA BROWN, CNN SENIOR WHITE HOUSE CORRESPONDENT: That's absolutely right. I did ask also about the political rhetoric surrounding all this. They wouldn't go there.

But Jeff Sessions, the attorney general, said, "Look, if you look at the targets, you look at the evidence out there with the social media, he is a partisan." He just came out there and said it.

And it is true. It's clear looking through his social media. He is a Donald Trump supporter. A MAGA supporter. In fact, we have images of him at a MAGA rally in Florida. He's holding up a "CNN sucks" poster there at that rally.

[17:10:08] So we have -- you know, you look through his tweets, several of the people targeted in these string of suspicious packages, these bombs, are people he's tweeted negatively about.

And then you look at the van, the suspect's van, where he was apprehended. There are several posters there critical of, again, some of the targets, including CNN, saying "dishonest media," a term we hear quite often from the president.

I was just speaking to one former prosecutor, Wolf, who said, just looking at the posters on the van, that would be enough you would need to prove motive here, what was behind this. As Jeff Sessions said, it was political violence.

BLITZER: Yes, he is. He was advertising on that van with all those -- all those stickers exactly where he stands politically.

We also showed, Jim, some video at a Trump rally where he was up there with a big poster saying, "CNN sucks." Clearly, that would explain why there were two of these bombs sent to CNN headquarters, CNN offices in New York.

SCIUTTO: You could debate and investigate the influence that this kind of material and rhetoric had on him. You don't know.

That said, there's a clear match here, right? A lot of the faces on that truck, as Pamela was saying, were faces that he targeted. You know, he had crosshairs on our colleagues, Van Jones, Michael Moore, et cetera. He had faces of the senators, Eric Holder, others who were targeted here.

So at least there is -- there is an overlap between the kind of stuff he was sharing, the kind of stuff he was driving around in the truck, and -- and the targets that he chose to target with these real IEDs.

And it struck me the similarity in some ways, or at least the parallels, to lone-wolf terrorist actors. ISIS folks, et cetera. You know, self-radicalized. They radicalized by things on the Internet, violent, Islamic terrorism.

This guy radicalized by violent intentions, you know, with domestic political targets, acting on his own. At least that's what's assumed at this point.

But parallels to the way lone wolves who do international terrorism. Here a domestic terrorist, in effect, who had a similar path.

BLITZER: The FBI director, Christopher Wray, he made it clear, these were not hoax or fake devices. These were real IEDs.

PEREZ: No, these were real IEDs. This is the big concern from the FBI. And that's why you see, even today. The fact that they were able to -- they found a device or package that was addressed to Kamala Harris, the senator, they immediately cleared the area. They evacuate people. They do the same thing for the package that is still being investigated in Burlingame, California, that was being -- that was addressed to Tom Steyer, the Democratic fundraiser, donor.

They have to treat this extremely seriously, because as you heard from Shimon, it's clear that there was enough in these components here that could -- someone could have been hurt. And that's what's important for people to remember here.

BLITZER: You know, Shimon, you were out front in breaking this story every step of the way. But were you surprised how quickly it all unfolded and the arrest of this guy occurred?

PROKUPECZ: Well, not today, Wolf. Certainly. You know, both Evan and I yesterday started hearing that there was considerable movement in the investigation, that law enforcement was pretty confident that they were going to get their guy. That they were going to come to a resolution.

Because, as we know, they identified him yesterday off of the Maxine Waters package, the package that was sent to Maxine Waters.

So up until really yesterday, really yesterday -- early yesterday evening, you know, Evan and I had this conversation. I called him, and I said, you know, "I'm hearing stuff is going to be happening." And so it was really -- everything changed yesterday, Wolf.

And then today, coming into this morning, I could sense, in just talking to law enforcement officials, that things were about to happen, and they were perhaps even just hours away from making an arrest in this case.

BLITZER: Yes, I could sense also yesterday when they said, "Guys, go focus in on Florida. There's a lot going on in Florida." All of a sudden, we began to realize that maybe this guy is in Florida. And guess what? He was.

Everybody stick around. There's a lot more we're watching. The bombing suspect is known to have attended at least one Trump rally, and the president is about to hold another one tonight in Charlotte, North Carolina.

Our senior White House correspondent, Jeff Zeleny, is on the scene for us already.

So Jeff, walk us through the president's reaction.

JEFF ZELENY, CNN SENIOR WHITE HOUSE CORRESPONDENT: Well, Wolf, just a short time ago, as the president was leaving the White House, he disavowed any relationship to this. But he would not answer our question if he should disavow the support of this man, this suspect, in Florida.

Now, the president throughout the day, you know, throughout the last several days, on one hand, he has been dismissing the acts. Today he called them terrorizing acts. He said they're despicable, and they have no place in our culture. But he did not say what he would do about it.

(BEGIN VIDEOTAPE)

ZELENY (voice-over): President Trump urging Americans to unify tonight. But refusing to acknowledge how his divisive rhetoric has contributed to an overheated and dangerous political climate and may have motivated bombing suspect Cesar Sayoc.

[17:15:06] DONALD TRUMP (R), PRESIDENT OF THE UNITED STATES: The bottom line is that Americans must unify. And we must show the world that we are united together in peace and love and harmony, as fellow American citizens.

ZELENY: But those words so far are just words. Not followed by action.

TRUMP: We must never allow political violence to take root in America. Cannot let it happen. And I'm committed to doing everything in my power, as president, to stop it. And to stop it now. Stop it now.

ZELENY: That's teleprompter Trump, with a carefully scripted message 11 days before the midterm elections.

TRUMP: These terrorizing acts are despicable and have no place in our country. No place.

ZELENY: But officials tell CNN the president does not believe he's complicit in contributing to the red-hot political atmosphere, where an apparent supporter allegedly sent package bombs to more than a dozen Trump critics.

And CNN has learned the president is telling allies and advisers that he doesn't believe it's fair to link his rhetoric to the attempted violence, despite the political leanings plastered in stickers on the suspect's van. The president made that point clear, when moments after saying he would do everything in his power to change the tone, he repeated what he's been saying all along and painted himself as the victim.

TRUMP: I call them fake polls. I can do the greatest thing for our country, and on the networks and on different things -- it will show bad. They will take it back -- yes, fake news. ZELENY: This morning, even as authorities in New York discovered

another package bomb and were closing in on the 56-year-old suspect in south Florida, the president diminished the threat, suggesting the serial bombing attempts were politically inconvenient.

"Republicans are doing so well in early voting and at the polls, and now this 'bomb' stuff happens. The momentum greatly slows," the president saying on Twitter. "News not talking politics. Very unfortunate what is going on. Republicans, go out and vote."

While the president put bomb in quotation marks, tonight FBI Director Christopher Wray, made clear the severity of the threat.

WRAY: These are not hoax devices.

ZELENY: At the Justice Department, forceful words from officials, reflecting the assassination attempt of the Obamas, Clintons and other Democratic officials and critics of Trump.

But the president, he was airing his grievances in the middle of the night on Twitter. At 3:14 a.m., writing, "Funny how lowly rated CNN and others can criticize me at will, even blaming me for the current spate of bombs and comparing this to 9/11 and the Oklahoma City bombing."

While Trump never shies away from calling out Hillary Clinton, Barack Obama, Joe Biden and others by name --

TRUMP: Lyin', Crooked Hillary.

He is a terrible, terrible president.

With Biden, you go like this. Whew. And he goes down.

ZELENY: -- and he routinely attacks CNN --

TRUMP: You watch the Clinton News Network, CNN -- it's a joke.

ZELENY: -- mentioned none of the targets by name today.

TRUMP: On the packages and devices that have been mailed to high- profile figures throughout our country and a media organization.

(END VIDEOTAPE)

ZELENY: Now, earlier this afternoon, Vice President Mike Pence did specifically call out Hillary Clinton and Barack Obama and CNN, saying that these acts of terrorism simply will not stand.

But Wolf, the central question is, what happens when the president reaches this rally here in Charlotte? I can tell you, the crowd is already very fired up. We've already heard many chants of "CNN sucks."

But we did get a sense of what the president may be thinking in his mind as he arrives here at the rally. Take a listen to what he said just a few minutes ago on the South Lawn of the White House when he was asked about his tone.

(BEGIN VIDEO CLIP)

TRUMP: I did not. I did not see my face on the van. I don't know. I heard he was a person that preferred me over others. But I did not see that.

Not at all. No. There's no blame. There's no anything. If you look at what happened to Steve Scalise, that was from a supporter of a different party. You look at what happened -- numerous of these incidents, they were supporters of others.

Well, I think I've been toned down, you want to know the truth. I could really tone it up. Because, as you know, the media has been extremely unfair to me --

UNIDENTIFIED FEMALE: How?

TRUMP: And to the Republican Party.

UNIDENTIFIED FEMALE: How?

TRUMP: I think the media has been very, very unfair in terms of the Republican Party and the way it's been covered. And they understand that. They write articles about that. Many of them admit that.

But the media has been unbelievably unfair to Republicans, conservatives, and certainly to me.

But with all of that being said, we're winning. So I like that.

(END VIDEO CLIP)

ZELENY: So it is that sense of grievance the president clearly has in his mind against the media. Now, he believes he is being treated unfairly. That is going on as he arrives here.

[17:20:00] Now, Wolf, it was striking. There were so many more stronger and more forceful words from the Justice Department today about the seriousness of these pipe bombs than, indeed, from the White House. But the president there saying, "I could tone it down, or I could turn it up."

So tonight in two hours, that is the question here. What will he do tonight in Charlotte, and what will he do for the next 11 days of this heated midterm election campaign -- Wolf.

BLITZER: All right. Jeff Zeleny in Charlotte, North Carolina, for us. Thank you very much.

We're getting some new information coming into THE SITUATION ROOM right now about a court date for the suspect. We'll update you on that and all the breaking news right after this.

(COMMERCIAL BREAK)

[17:25:05] BLITZER: We're following the breaking news: the arrest in Florida of a suspect in a series of bombs mailed around the country.

A law enforcement official tells CNN the man, Cesar Sayoc, 56 years old, was living in his van, its windows plastered with pro-Trump signs and other stickers. His social media accounts also contain postings that are stridently partisan.

We have a lot to discuss once again with our experts.

And Pamela Brown, let me walk you through some of the postings, some of the stickers on that van and some of his other postings. Take a look at this: George Soros, one of the individuals, a wealthy billionaire, who received one of those IEDs: "World is waking up to the horrors of George Soros."

Look at this. He goes after what he calls the swamp to be drained, and he's got a lot of pictures, including several of individuals who were targeted by these IEDs.

Then there's a Twitter -- a tweet posting in which he says, "Hey CNN, all B.S. con job, fraud puppets," and he goes on and blasts CNN.

You see him there standing with a card, with a big poster saying "CNN sucks" at one of the rallies.

Then there's one that specifically attacks the former president, Barack Obama. "Is this the greatest fraud played on the American people," he says.

And finally, another one on George Soros, in which he goes after him and other various think tanks, political organizations like Media Matters, mainstream media, Center for American Progress, and makes all sorts of accusations.

All these postings, these tweets, they're valuable evidence for law enforcement.

BROWN: Valuable evidence. As one official I just spoke with said, "Look, these are his words. This is his confession, essentially, in terms of a motive." In fact, it's so important that it's listed here in the criminal complaint that was released today.

The law enforcement official listed his Twitter account, saying that there were various posts with misspellings such as spelling "Hillary" with one "L" that corresponded with some of -- with the packages that were sent out.

So you had the misspellings. You had a post dated October 24, a negative post against President Barack Obama and George Soros. This was after the package to George Soros was recovered.

So this is important evidence in the investigation in terms of the why, the motive. One official I was speaking with said, if you look at the posters on his van that correspond with a lot of the targets from the mail bombs, that is essentially explaining the motive here. That's all I would need as a prosecutor to explain the motive. You see the CNN sign there with Van Jones, one of our colleagues, with

the crosshairs. I mean, this shows you, he is partisan, as we heard from Jeff Sessions today. Pretty amazing admission from the attorney general that, "Look, this guy is partisan. Clearly, this was an act of political violence," as he said in his words.

BLITZER: And Gloria, a lot of these posts are all over social media by other right-wing conservative groups.

GLORIA BORGER, CNN CHIEF POLITICAL ANALYST: Well, right. Look, you know, this -- this man didn't really try to hide his obsessions. Right? And so he advertised it. And you know what happens on Twitter. Things get picked up. He also picked up things from right- wing media and retweeted it from right-wing publications.

He drove a van that was plastered with his obsessions against these people and CNN. And so he -- it wasn't -- he was trying to connect, in an odd way, with like-minded people. He wanted to advertise his views on social media. Luckily, for the FBI and everybody else who's indicting him.

But, you know, I think that -- that he broadened himself. He tried to create a community, in an odd way, for himself. And maybe he did. We just don't know yet.

BLITZER: And he made it clear, you know, unlike some far-right elements out there who, over the past several days, we're saying this was probably a false flag operation. Some liberals were really doing this to make the president look bad. This was no false flag operation.

SABRINA SIDDIQUI, "THE GUARDIAN": Well, quite clearly not. And that's what authorities wanted to make very clear today.

And the challenge is, of course, that there continues to be a deep mistrust of the institutions on the far right. And so is that going to change some of the minds of those who have pushed conspiracies? Probably not. And that's where the president's role is so key.

Earlier today, the president tweeted about the attempted bombings, and he put the word "bomb" in quotation marks. What he intended to do, only he can answer. But he appeared to be casting doubt, or at least expressing some skepticism over the nature of this mailing campaign and the way in which officials were targeted.

And that does, then, give rise to some of these conspiracy theories -- theorists on the right, particularly as we go into midterm elections. And it's, frankly, very dangerous, because it doesn't make explicit, from the office of the presidency, what the true gravity of the last 48 hours have been.

BLITZER: Anthony Ferrante is with us, especially, former FBI agent, a bomb technician.

I want to show our viewers. We've got some live pictures coming in right now. [17:30:00]

Authorities are searching the home in Aventura, Florida. That's right near Hollywood, North Miami Beach, in Aventura, Florida, the home of his mother, where he was currently living for a while. He was kicked out by his family. What are they looking for, do you suspect?

ANTHONY FERRANTE, FORMER FBI SPECIAL AGENT BOMB TECHNICIAN: So, right now, now that they have this custody -- now that they have this person in custody, what they're doing is building their case. They're going to every place where he's ever been. His place of employment, his van, which I understand he may have lived out of, his former house. And they are collecting clues to build their case. Right? All the evidence they can collect so they can then take him to court. They -- it's my understanding they haven't definitively identified this laboratory in which they made these devices. That's going to be a huge clue for them. And really help them build their case as they look to prosecute this individual.

BLITZER: You think there is serious concern others are still at large, and may be involved in this, and that there's still yet other bombs out there?

FERRANTE: Well, wolf, that's an interesting question. I mean, you look at -- you show us those photos, and it's very clear that this individual thought that he was part of a larger cause. Right? And I think that is -- that is a sign of potentially times to come. I mean, it's very troubling. He clearly thought he was part of something. Right? He took his individual beliefs and thought that he was doing something for the greater good. Which is troubling. And it's a signal to law enforcement. They need to be aware and on the lookout for individuals like this.

BLITZER: All right. Everybody standby. There's a lot more information coming in right now. This is a fast-moving story. We'll take a quick break. We'll be right back.

(COMMERCIAL BREAK)

[17:36:17] BLITZER: We're following the breaking news, the arrest in Florida of the suspect in the series of the bombs mailed around the country. During a news conference this afternoon, the FBI Director, Christopher Wray, explained how investigators connected the bombs with the suspect.

(BEGIN VIDEO CLIP)

CHRISTOPHER WRAY, DIRECTOR, FBI: Each device consisted of roughly six inches of PVC pipe, a small clock, a battery, some wiring and what is known as energetic material, which is essentially potential explosives and material that give off heat and energy through a reaction to heat, shock or friction. Though we're still analyzing the devices in our laboratory, these are not hoax devices. I want to focus for a moment on the amazing work of our folks at the FBI lab.

Based on their initial analysis, they uncovered a latent fingerprint from one of the envelopes containing an IED that had been sent to Congresswoman Maxine Waters. We have confirmed this fingerprint is that of Cesar Sayoc. There is also a possible DNA connection between samples collected from pieces of two different IEDs mailed in separate envelopes, and a sample previously collected from Sayoc in connection with an earlier arrest down in Florida.

(END VIDEO CLIP)

BLITZER: All right. So, Anthony, you understand precisely what the FBI -- you used to work at the FBI, what the FBI director is saying right now. It sounds a little complicated, but all of us know what IEDs are. Those of us who've covered wars in Iraq, for example, improvised explosive devices. We know how many American troops and others lost legs, lost arms or were killed by IEDs.

FERRANTE: Yes, Wolf. Absolutely right. I mean, Director Wray did an excellent job of explaining what these devices were. For the last few days, I've been listening to reporting about how these were rudimentary devices. That's really all it takes, OK? This is volatile material contained very tightly within these PVC pipes. And he said it exactly right. Spoken like a true bomb technician. Heat, shock, friction. That's all it takes. You could take that containment and just shake it very quickly, and just that would be enough friction to ignite that material within that pipe and that alone would create an explosion and create shrapnel that could easily kill somebody.

BLITZER: And Pamela, you were there at the Justice Department for that briefing with the FBI director and the attorney general and others. Walk us through a little bit of the background, how significant this development is.

PAMELA BROWN, CNN SENIOR WHITE HOUSE CORRESPONDENT: Well, I think, also, just to set the stage here. The press conference happened just hours after the president sent out this tweet about the, quote, bomb stuff overshadowing the momentum he had. And then you go to this press conference with the director of the FBI saying, this was not a hoax device. This was serious. The criminal complaint says that the intent was to use it to kill, injure and intimidate individuals. This was serious, which is why it was the highest priority in the FBI and other law enforcement agencies to find the perpetrator.

In this case, yesterday, things really started to progress. They started talking to law enforcement officials, getting a sense, all right, they're narrowing in on who this could be. And a big part of that is because of the fingerprint that was found on the device that was in the Maxine Waters package. Also, there was a potential DNA hit on another device that was sent to President Obama. They also had information about the cell phone that he had used that hit a tower nearby the facility where these packages went through. All of this started to come together last night and then, as you saw, they made the arrest this morning.

BLITZER: And Gloria, you just heard what Anthony said. Some shaking of those packages could have triggered an explosion, which could have killed or severely injured a lot of people. GLORIA BORGER, CNN CHIEF POLITICAL ANALYST: Exactly.

BLITZER: Yet just a few hours before the arrest, the president was tweeting about this so-called bomb stuff saying forget about the bomb stuff in effect, you know, you've got to focus in on the politics, because there is an election coming up.

BORGER: Yes, I mean, the president, you know, three times today, at the event, you know -- first of all, he tweeted about the so-called bomb stuff, which he put in quotes. Then an event at the White House, when, you know, this was announced, he started talking again about the campaign and interrupting his momentum, et cetera, et cetera. And then on the south lawn today, and Wolf, I think we may have --

BLITZER: Let me play the clip.

BORGER: Some audio.

BLITZER: This is what the president said.

BORGER: Yes.

BLITZER: Precisely. Listen to this.

(BEGIN VIDEO CLIP)

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: I think that we're running a great campaign. People love what we're doing. They love what we're saying. The Republicans had tremendous momentum, and then, of course, this happened, where all that you people talk about was that. And rightfully so. It was a big thing. Rightfully so. But now we have to start the momentum again.

(END VIDEO CLIP)

BLITZER: Yes.

[17:41:00] BORGER: Well, he's a victim here, obviously. Because this attempt to effectively assassinate two former presidents, a former secretary of state, a former attorney general, go on and on, interrupted the campaign. And he kind of can't get beyond that. He can't get beyond that to say, wait a minute. This was really important. He said, and rightfully so. It was a big thing. No, no. It was more than a big thing. It was a momentous thing.

And if it interrupted the campaign -- I mean, come on. He just can't get beyond that. And I think you can script the president all you want. You can script him today at that event at the White House. But when he tweets and when you hear him on the south lawn, it's what he's really thinking. And what he's really thinking is, woe is me. We were going to win x, y and z senate races and now boom. What are my rallies going to be like?

And, you know, they're chanting all over -- you know, what's he going to do when they chant "CNN sucks" today at this event in the White House. It was chanted. And what happened? Nobody told them to stop. So, you know, you can see the real Donald Trump there. And maybe his staff intends to try to get him to tone down. Who knows. But that's -- that's just never going to happen.

BLITZER: Sabrina, in the days leading up to this, some on the far right, you know, had really outrageous comments and tweets. Lou Dobbs, for example. He tweeted at one point, "Fake news, fake bombs. Who could possibly benefit by so much fakery?" He later deleted that tweet. Ann Coulter tweeted, "From the Haymarket riot to the Unabomber, bombs are a liberal tactic." That's the kind of stuff the president listens to and what he hears, but it's clearly ridiculous.

SABRINA SIDDIQUI, POLITICAL REPORTER, THE GUARDIAN: And it's not just that he listens to and hears these far-right conspiracy theories. He gives credence to them. And we've talked about his tweet today. Even to stop on the south lawn and talked about how this came at a time when Republicans had all this momentum ahead of the midterms. That is essentially the premise of the conspiracy theory that this was some sort of false flag planted by people on the left, to try and undercut Republicans ahead of the election.

So even as he is saying in one breath, we're taking this seriously, we're going to hold people accountable, in the very next breath, he is sort of still casting doubt around the circumstances. And I think that what's very concerning to many people is that a lot of these voices -- mostly operated in the prior years on the fringe. But increasingly, with the rise of this president, they have very much become part of the mainstream. And that is what is particularly dangerous, especially as we weigh the president's response to this act of what authorities have so clearly said is domestic and political terrorism.

BLITZER: You see -- go ahead.

GLORIA: I was going to say, let me emphasize this. Nobody is saying or would say that this is the president's fault. Period. End of sentence. Nobody would say that. But I think you have to take a step back and question what kind of political environment has been created, because everybody who's targeted is on the president's enemies list.

BROWN: Yes.

BORGER: And so that's the thing that the president --

BLITZER: what are you hearing, Pamela, from your sources at the White House? Any chance the president and his top advisers will back down a little bit right now and deal with this in a more constructive way, in a more presidential way?

BROWN: No. And I mean, you heard the president just today say, look, I've turned down the rhetoric, I can turn it back up, saying I could go either way. And officials I've been speaking with, just asking simple questions, such as why won't the president name the targets? Why does the president go after CNN all of the time or say, you know, CNN fake news, but won't say that the bomb was sent to CNN, just that it was -- belonged to a member of the media? And they pushed back very forcefully. The White House -- the

president and those working there feel like they're constantly under siege, and the attitude is that they're sort of the victims here. That they have been unfairly targeted by the media. So, I don't think you're going to see the president or anyone else in the White House, for that matter, back down or take any responsibility for, as Gloria said, the rhetoric creating this political environment that we're in.

BORGER: And can I just say one more thing? Why wouldn't this president of the United States call two former presidents, a former secretary of state, anybody who was on that target list and sent a bomb and say, we're on it? Not necessarily today. But when this first occurred? And he said, well, they wouldn't want to hear from me. But the role -- these are former presidents. And he still did not pick up the phone?

[10:45:44] SIDDIQUI: And he said, if they wanted to, we'll probably pass. Which is such a remarkable statement to make. And he not only has not named the targets, but he also has -- as you said, he's toned down his rhetoric. He's continuing to attack CNN in an early morning tweet, just days after the offices in New York were evacuated because an explosive device was sent to CNN. So, he's actually very much continuing to engage in attacks on the media. Nothing has changed.

BLITZER: The tweet was at 3:00 a.m. in the morning, the attack on CNN. He was clearly up in the middle of the night. Everybody, stick around. There's more on the breaking news we're following. The arrest of a suspect in a series of package bomb mailings. Authorities are also warning, more bombs could still be in transit, which puts the focus directly on a seldom-recognized branch of law enforcement. Stay with us for a closer look at the crucial role played by postal inspectors

(COMMERCIAL BREAK)

[17:51:11] BLITZER: We have much more ahead on breaking news. Today's arrest of a suspect in this week's series of package bombs mailed around the country, CNN's Brian Todd has a closer look at a seldom-recognized branch of law enforcement that played a very crucial role in the investigation. Brian, tell us more.

BRIAN TODD, CNN CORRESPONDENT: Wolf, that branch is the U.S. Postal Inspectors Police Division. We've learned they've been at the forefront of this investigation from the start and they're actively involved tonight because officials say there could still be more bombs moving through the mail system.

(BEGIN VIDEOTAPE)

TODD: On the ground, with FBI agents in Florida as the suspect's van was being processed, U.S. Postal Inspector Police.

FELIX NALER, FORMER U.S. POSTAL INSPECTOR: They're a major component of this investigation. Probably safe to assume they were monitoring, tracking the suspicious parcels after they were informed by the well- trained postal employees around the nation. So, they're there because they're part of that team.

TODD: Felix Naler was a U.S. Postal Inspector for 26 years. His concern tonight, even with the arrest of the suspect, Cesar Sayoc, more bombs could be in the system.

NALER: We're hoping the heightened sense of awareness would put people on queue to be more aware and alert of anything that might be suspicious.

TODD: Naler won't give away specific techniques for screening bombs, but he and current postal service officials say they have sophisticated screening devices, surveillance cameras to monitor suspicious behavior and elite members of the postal inspector police looking for explosives.

GARY BARKSDALE, U.S. POSTAL INSPECTION SERVICE: These dangerous mail investigation specialists are highly proficient in the use of state- of-the-art equipment.

TODD: What patterns do those specialists look for in dangerous packages?

NALER: They're in certain styles, there's patterns of writing on the face of the envelopes or the mailings. There are indicators of suspicious behavior that at least begins the suspicious inquiry as to what's going on here.

TODD: Naler says, whether it's discovered on the sending or receiving end, any suspicious package is quickly and carefully isolated. A key question tonight, how would some of the mail bombs this week have gone through the mail system to their destinations without cancellation marks on the stamps. Naler says those cancellation marks are done by machines which aren't fool proof.

NALER: It may not show up at all if it goes through a machine and it's not the right dimensions.

TODD: Post Office officials say, it's not just the postal inspector police who are on the lookout tonight. Some 600,000 postal service employees across the U.S. are now in effect investigators. Are they in danger from possibly more bombs still in the system?

NALER: If it doesn't get identified and it makes it through the system, and somebody unintentionally mishandles it, the devices improperly, or designed by an amateur and it explodes, there can be ancillary damage to those that might be in the area.

(END VIDEOTAPE)

TODD: Naler says enhanced security measures are going to be put in place. They're in place right now to protect postal service employees while there may still be threats inside the system. And he says, U.S. Postal Inspector Police very likely did take part in the initial interrogation of the suspect, helping to gain intel convenience from him. The postal inspector police didn't respond to our inquiries about what they might have been after, though. BLITZER: You know, Brian, these Postal Service Police have elite

training and powers similar to other police and the FBI, right?

TODD: That's right, Wolf. We're told that postal inspector police, they can make arrest, they can serve warrants, they do extensive firearms training, threat-management training and not many of those who try out for those units get selected. They're pretty elite units, Wolf, because there have been so many incidents in the postal system through the decades.

[17:54:39] BLITZER: We are so grateful to all of them, for the critically important work they do. Brian Todd reporting, thank you very much. Breaking news continues, next with more on the arrest of a suspected serial bomber believed to be behind at least 13 pipe bombs. Tonight, we are learning new information about him and the explosive devices.

(COMMERCIAL BREAK)

BLITZER: Happening now, breaking news. Bomb suspect charged. A Florida man arrested and accused of sending more than a dozen explosive devices to prominent public figures who have been criticized by the president. We are learning more about him and his lengthy criminal record.

Real and present danger. The FBI chief wants the public to know that these bombs were not hoaxes and that more of them could be out there in the mail, potentially threatening lives.

Pro-Trump post. The suspect's van offering clear evidence that he's a supporter of the president and an opponent of many Democrats.